Power-operated hand tool



Oct. 24, 1950 A W, SMH-H POWER-OPERATED HAND TOOL Filed July 12, 194e nwm R mm NN rrowin Patented Oct. 24, 1950 I' UNITED STATESPATENT OFFICEPOWER-OPERATED HAND TOOL Arthur W. Smith, Los Angeles, Calif., assignerof one-half to M. Duke Lanfre, Los Angeles, Calif.

Application July 12, 1946, Serial No. 683,291

(Cl. 741-44) Y 3 Claims. 1

The present invention relates to power tools in general and particularly'to a hand-carried 1motordriven power tool. More specifically theinvention comprises a power-operated hand tool provided with drivingmeans for rotary and forl reciprocatory working elements.

Power-operated hand tools are of great value in many types of work.Their weight enables them to be moved readily from place to place andbeing relatively small they can be used in surroundings preventing theuse of more cumbersome tools. Additionally they are desirable in thatthey are capable of performing many operations in a time period only afraction of that required to perform the same operation by hand.

Certain operations require a rotary work-contacting element while othersmake better use of a reciprocating element. Power-operated hand tools inthe past have been adapted to drive one or the other type but none hassatisfactorily provided a power source for both rotary andreciproc'atory elements. The advantage of having one tool capable ofproviding both motions is clear and results not only in an investmentsaving but also in a time saving in that a simple exchange ofwork-contacting elements upon the same power tool is all that isrequired.

With the foregoing disadvantages of the prior art in mind, it is anobject of the present invention to provide a new and improvedpoweroperated vhand tool adapted to actuate both rotary andreciprocatory work-contacting elements.

It is a further object of the invention to provide a motor-driven powertool adapted to be `carried in the hand in which reciprocatory or rotaryworking elements can be selectively attached and actuated.

These and other more specific objects will appear upon reading thefollowing specification and claims and upon considering in connectiontherewith the attached drawings to which they relate.

Referring now to the drawings in which a preferred embodiment of theinvention is illustrated:

Figure 1 is a view in perspective of a tool constructed in accordancewith the present invention, both rotary and reciprocatory workingelements being attached for purposes of illustration only;

Figure 2 is a longitudinal section through the tool constructed inaccordance with the present invention, a reciprocatory working elementbeing operatively connected; and Y Figure 3 is a partial section uponthe line 3-3 of Figure 2 showing the cam-actuating means forming a partof the reciprocatory drive.

The power-operated hand tool constructed in accordance with the presentinvention comprises several principal parts including an enclosingcasing II, a handle I2 attached at one end of casing II, a driving motorI3 positioned in the casing, speed reducing power transmitting means I4(connected to motorV I3, and the rotary and reciprocatory actuatingelements I6 and I1 which extend from the casing at its end spaced fromhandle I 2.

The tool casing, indicated generally by the reference character I I, ispreferably cylindrical and closed at one end by an integral convex wallI8. Its opposite end is closed by a removable plate I9 formed integrallywith a frame 2| seated in a gear box or housing 22, the rear wall 23 ofwhich divides the casing II into a motor compartment and a powertransmission compartment. Frame 2| is secured within the gear housing 22by means of set screws 24 and both are removably secured in casing II bymeans of one or more set screws 26.

The driving .motor for the unit is positioned within the motorcompartment formed between the walls I8 and `23. Its stator 3| iscarried by casing I while its rotor `32 is mounted upon shaft 33rotatable in bearings 36 and 31 in walls I8 and 23, respectively. Aswitch 38 is carried by handle I2 andthe leads 39 to the motor extendtherethrough, the flow of current to the motor being controlled by theswitch. To insure adequate motor cooling casing I I is provided withcircumferentially spaced openings 4| for the'circulation of yVentilatingair.

The speed reducing and power rtransmitting means are positioned withinthe gear box 22 into which the motor shaft 33 extendsa pinion 42, beingcarried in its end. Frame 2|, which supports those means, includes acentral supporting wall ll midway between curved side walls '4l and 48,the latter lying against the side wall of gear box 23, and an end wall49. The spaces between the aforementioned walls, and in fact the entirespace within gear box 22, is preferably filled with suicient lubricantor grease to insure quiet running and long life of the moving partspositioned therein.

A longitudinally extending driven shaft 5| is rotatably mounted in framewall 49 by a bearing 52 and carries, rearwardly of wall 49, an internalring gear 53. Upon the inner side of gear 53 and meshing therewith, isan eccentrically mounted intermediate gear v55| which also meshes withthe pinion 42 on the motor shaft 33. Rotation of shaft 33 and pinion yI2effects rotation of intermediate gear 54 which in turn drives ring gear53 fixed upon shaft 5I, to cause the latter to rotate at a reduced speeddetermined by the ratio of the gears. Upon the opposite side of wall 49shaft 5| carries a bevel gear 56 and at its end forwardly thereof isreduced in size and given an irregular section as at 51 in order to seatiixedly in the recessed end of the tool-actuating shaft I6 rotatablymounted in a bearing 59 in front wall I9. Shaft I6 extends forwardlythrough Wall I9 which is formed therearound on its outer face with asurrounding boss BI threaded internally and externally. A -hexagonalheaded gland 62 is threaded into boss 6I to provide a seal around theshaft and, as clearly shown in Figure 2, a protecting cap -63 is adaptedto be screwed onto the threaded exterior of the boss when a working toolelement is not connected. When a rotary tool is to be actuated the cap63 is removed and a Jacobs chuck 56 is forced onto the end oftool-actuating shaft I6, its jaws 51 seating a work contacting elementsuch as a drill 58 shown in Figure l.

Within the gear case 22 a transverse driven shaft 'II is rotatablymounted in bearings 'l2 and 13 positioned in walls 46 and 48,respectively. To connect it to longitudinal driven shaft 5I it carrieson its inner end a bevel gear 'I4 meshing with gear 56.` Centrally andbetween longitudinally extending walls 46 and 43 shaft 1I carries an ec-:u

centric cam 'I6 rotatable therewith and enclosed by a ring follower, TI.The latter is extended upon one side in the form of a bifurcatedextension 'I8 connected by a pvot pin 'I9 to the reciprocatory toolactuating plunger or rod I'I. The latter extends parallel to the rotarytool actuating shaft I6 and passes outwardly through the front plate I9in which it is slidably supported by a sleeve bushing 84. As in case ofshaft I6, forward plate I9 is formed with an encircling boss 82 aroundrod I1, a boss which is threaded internally and externally and which is,in the manner of boss 5I, sealed internally by means of the gland 83.The outer end of rod I1 is preferably threaded as at 86 and so adaptedto seat an internally threaded sleeve 8T comprising the attaching end ofan arm 88 pivotally connected to a reciprocatory tool 89 which, asillustrated, is a sander. The latter is readily disconnected Ibyrotating sleeve 8T and thereafter, if desired, a

protective cup like the cup 63 may be screwed upon the boss 82. v

In operation the current-conducting leads 39 are connected to a suitablesource of electrical current. Depending upon the type of work to beperformed, the operator removes the protective cup which encloses theends of element I6 or I1 to-expose it. Element I6 is selected if arotary work contacting element is to be driven, a J acobs chuck isforced onto the end thereof, and the operative tool element secured inplace by closing the chuck jaws. If however a reciprocatory element isto be driven, the protective cup or thimble is removed from the threadedboss 82 to expose the end of reciprocatory rod I1 and the workingelement connected thereto. The closing of the manually operable switch38 then effects the energization of the driving motor I3 whereupon thearmature 32 and shaft 33 rotate and with them the pinion gear 42.Concomitantly the planetary drive rotates the ring gear 53 at reducedspeed and as the rotary shaft 5| is fixed relatively thereto, it, andwith it shaft I6, also rotates. Transversely extending driven shaft TI,being connected through bevelled gears 54 and 56 to the longitudinallyextending shaft 5I, is also rotated. Its rotation effects thereciprocation of the reciprocatory rod I'I which moves inwardly andoutwardly relative to the casing. If a rotary working tool has beenconnected to shaft I6 it is rotated. If a reciprocating tool has beenconnected to rod II, then it is reciprocated. The tool is easily stoppedand started for the change of working tools by the manual operation ofthe control switch 33 and a change from rotary to reciprocatory tools,or vice versa, is readily accomplished in the manner described.

While the particular apparatus herein shown and described in detail isfully capable of attaining the objects and providing the advantageshereinbefore stated, it is to be understood that it is merelyillustrative of the presently preferred embodiments of the invention andthat no limitations are intended to the details of construction ordesign herein shown other than as defined in the appended claims.

I claim:

1. A power-operated hand tool comprising: an elongated casing open atthe forward end and having a handle on the rearward end; a driving motorinthe rearward portion of said casing having a shaft substantiallycoaxial therewith; a journal bearing mounted in the rearward end of saidcasing to rotatably support the rearward end of said motor shaft; a gearhousing having an open forward end flush with the forward end of saidcasing, said housing being positioned within said casing and having arearward wall extending entirely across the interior of said casing,said housing wall having a journal bearing therein to support theforward end of said motor shaft with said motor shaft extending throughsaid wall; a removable frame secured in the forward portion of said gearhousing, said frame having a rearward wall extending entirely across theinterior of said gear housing and being forwardly spaced from said rearwall of said housing wall whereby to form therewith a first sealedtransmission chamber adapted to receive a body of lubricant, and saidframe having a forward closure plate positioned and adapted to close theforward ends of said casing and gear housing and to form a secondtransmission chamber ahead of said frame wall; a first longitudinalshaft rotatably mounted in said second chamber, said rotatable shaftextending rearwardly through said frame wall into said first chamber andforwardly through said plate to project from the front of said casing; asecond longitudinal shaft recipro-cally mounted in said second chamberand extending forwardly through said plate to project from the front ofsaid casing; a gear transmission positioned in said rst chamber andoperatively connected between said motor and rotatable shafts to effectreduced speed rotation of said rotatable shaft; and reciprocating meansin said second chamber including a transverse shaft j ournaled in saidframe and geared to said rotatable shaft and an eccentric on saidtransverse shaft to effect reciprocal motion of said second longitudinalshaft as a result of rotation 0f said first shaft.

2. The construction of claim l further characterized in that each ofsaid first and second shafts is formed with detachable means forconnecting tools to the forward ,ends thereof.

3. The construction of claim 2 further characterized by having a pair ofidentical threaded bosses formed on the front of said closure plate, onesurrounding each of said first and second 5 shafts and an interiorlythreaded protecting cap secured to one of said bosses whereby to enclosesaid shaft therein.

ARTHUR W. SMITH.

REFERENCES CITED The following references are of record in the le ofthis patent:

Number 6 UNITED STATES PATENTS Name Date Verneuil Apr. 11, 1922 HageAug. 14, 1923 Miller July 5, 1927 Harvie Feb. 21, 1933 Johnston Dec. 6,1938 Mastrud May 21, 1940 Toop Nov. 5, 1940 Lovelace Dec. 30, 1941

